S-812C36AUA-C2Q-T2 Просмотр технического описания (PDF) - Seiko Instruments Inc

Номер в каталоге

Компоненты Описание

производитель

S-812C36AUA-C2Q-T2

HIGH OPERATING VOLTAGE CMOS VOLTAGE REGULATOR

Seiko Instruments Inc 

Rev.1.0

HIGH OPERATING VOLTAGE CMOS VOLTAGE REGULATOR

S-812C Series

„Application Circuits

1. Output Current Boost Circuit

As shown in Figure 11, the output current

Tr1

can be boosted by externally attaching a

PNP transistor. The S-812C controls the

base current of the PNP transistor so that the

output voltage VOUT becomes the voltage

specified in the S-812C if the sufficient base-

emitter voltage VBE to turn on the PNP

transistor is obtained between input voltage

VIN and S-812C power source pin VIN.

VIN S-812C

VOUT VOUT

VIN

R1

Series

ON/OFF

VSS

CIN

CL

GND

• As the transient response characteristics

Figure 11 Output Current Boost Circuit

of the circuit shown in figure 11 is not enough in some applications, evaluation for output variation due to

power-on, power line variation and load variation in actual condition is needed before massproduction.

• Note that the short-circuit protection incorporated in the S-812C series does not work as a short-circuit

protection for the boost circuit.

2. Constant Current Circuit

The S-812C series can be served in a

constant current circuit as shown in the

figure 12. Constant current IO is calculated

from the following equation:

IO = (VOUT(E) ÷ RL) +ISS, where VOUT(E) is

the effective output voltage.

Please note that in case of the circuit

shown in the figure 12 (1) the magnitude of

the constant current IO is limited by the

driving ability of the S-812C.

The circuit shown in the figure 12 (2) can,

however, provide the current beyond the

driving ability of the S-812C by combining a

constant current circuit with a current boost

circuit. The maximum input voltage for the

constant current circuit is the sum of the

voltage VO of the device and 16 V. It is not

recommended to attach a capacitor

between the S-812C power source VIN

and VSS pins or between output VOUT

and VSS pins because rush current flows

at power-on.

(1) Constant Current Circuit

VIN

VIN S-812C VOUT

Series

VSS

ON/OFF

CIN

GND

RL V0

IO

VO

Device

(2) Constant Current Boost Circuit

Tr1

VIN

GND

S-812C VOUT

R1 VIN Series

VSS ON/OFF RL V0

CIN

Io

VO

Device

Figure 12 Constant Current Circuits

3. Output Voltage Adjustment Circuit

The output voltage can be increased using the configuration shown in the figure 13. The output Voltage VOUT1

can be calculated using the following equation;

VOUT1 = VOUT(E) x (R1 + R2) ÷ R1 + R2 x ISS,

where VOUT(E) is the effective output voltage.

Value of R1 and R2 should be determined so as not to be affected by the current consumption ISS.

Seiko Instruments Inc.

9

Share Link: